The bar analogy is interesting but is missing the most important factor: All of the bars have the same name. The only difference is where they are located. Now I have to go to each one because I have no idea if they’re a soccer themed bar or a karaoke bar.
Even if the redundant communities somehow solve themselves (which I doubt), there will forever be an abandoned community polluting the search results because no one is going to delete it.
When I look at the many communities with the same names, I completely stops me from interacting with them. Most of the time I know they’re going to be copies of each other with a bunch of duplicate content reposted to infinity.
I think your example is interesting but i disagree with your assertion that it some how facilitates finding niche content.
For example it would be difficult to have to explicitly know that obscure-instance.xyz/c/games hosts content about 90’s graphic adventure games from the Netherlands and programming.dev/c/games is actually about game design and not games generally. A better way, IMO, is to just name your community what it is. Names likeadventure_games_nl and game_design offer a significantly better user experience. If we want to make the fediverse feel accessible to people, it has to be easy to find what you’re looking for.
This whole thing feels like crypto where everyone has their own coin and they only kind of work together if you have some kind of exchange and some people accept Bitcoin and not Doge. It’s just too complicated for non technical people.
A good thing to note is that both of those bars you mentioned have different names. That makes it easier to know which to go to, once I figure out which is which.